Transient Protection Based on Rogowski Coil Resonance Theory and Wavelet Energy Spectrum

Abstract:

The paper presents a new single terminal transient protection scheme for distribution network based on Rogowski coil resonance theory and wavelet energy spectrum. The transmission characteristics of transient signal of the line boundary were changed by introducing Rogowski coil resonance equipment, and the internal fault was distinguished from the external fault. Consequently, an immediate trip was realized among the distribution network. After determining the fault moment by wavelet modulus maxima, the high and low frequency band signals in the fault period were extracted so that a reliable protection criterion was obtainted by calculating ratio of high frequency energy and lower frequency energy. Finally, PSCAD/EMTDC simulation results prove the effectiveness of the proposed protection scheme, which is reliable to discriminate internal and external faults under different conditions.